Brake mechanism for trucks.



PATENTED JULY 25, 1905.

B. R. STARE. BRAKE MECHANISM FOR TRUCKS.

APPLIOATIOH FILED NOV. 16, 1901.

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PATENTED JULY 25, 1905.

B R STARE BRAKE MECHANISM FOR TRUCKS.

APPLICATION FILED NOV.16, 1901.

. EZ/JMW WITNESSES:

UNITED STATES PATENT OFFICE.

BURTON R. STARE, OF KINGSTON, NEW YORK, ASSIGNOR TO PEOKHAMMANUFACTURING COMPANY, OF NEW YORK, N. Y., A CORPORATION OF N EWV YORK.

BRAKE MECHANISM FOR TRUCKS- Specification of Letters Patent.

Patented July 25, 1905.

To all whmn it warty concern:

Be it known that I, BURTON R. STARE, residing at Kingston, in the countyof Ulster and State of New York, have invented certain new and usefulImprovements in Brake Mechanism for Trucks, of which the following is afull, clear, and exact description, such as will enable others skilledin the art to which it appertains to make and use the same.

This invention relates to brake mechanism for trucks, and is especiallyadapted for use with maximum-traction trucks or trucks adapted to becarried in pairs under the carbody, in which the load is unequallydivided between the different sets of wheels.

The object of the invention is to provide an improved means whereby thebraking pressure may be properly proportioned between the wheels of suchtruckthat is, may be so proportioned that the wheels which carry thegreater part of the load may receive the greater braking pressure.

To this end the invention consists in the features of construction,combinations of elements, and arrangement of parts, as will be morespecifically set forth hereinafter and the novel features thereofdefined in the claims at the end of this specification.

The invention will be understood by reference to the embodiment thereofshown in the accompanying drawings, in which Figure 1 is a longitudinalvertical sectional View showing conventionally the wheels, side frame,and car-body supports of a truck with my improved brake mechanismapplied thereto. Fig. 2 is a top plan showing in detail the variousparts of the brake mechanism, other parts of the truck being omitted forthe sake of clearness of illustration. Fig. 3 is a detail showing thebrake mechanism in end elevation looking from the right of Fig. 2 withcertain parts in section.

Similar reference characters refer to similar parts throughout theseveral views.

In the drawings I have shown my invention as applied to a four-wheeltruck of the maximum-traction type, having two large and two smallwheels, with the large wheels leading. It will be understood, however,that I am not limited to this specific type of truck, as my invention isapplicable to various types of trucks in which it may be .desirable toprovide means for obtaining a differential braking pressure or a brakingpressure which is divided unequally. It will also be seen that there arespecific advantages in the present form of brake mechanism (applicableboth to trucks wherein it is desired to divide the braking pressuredifferentially between the wheels and also to those wherein brakingpressure is not so divided) in that the various levers by which thebraking pressure is applied are for the most part arranged insubstantially hori- Zontal planes in such manner that they do notinterfere with the other parts of the complete truck and motorequipment. By horizontal plane is meant that the levers with referenceto the truck-frameextend transversely from their pivotal points ratherthan above and below. Obviously this could be provided for in the caseof levers formed of bars such as those shown in the present illustrationby pivoting them either upon vertical or transverse pivot-pins. Ineither event they would be distinguished from levers which extend aboveor below their pivotal points whether in a vertical or inclined plane.

Referring first to Fig. 1, the side frame of the truck is represented atA. B B are the axles carrying the large wheels O and small wheels D.TransomsEare properly supported upon the side frames, and between saidtransoms is guided bolster F, which may be supported in any desired way,as upon elliptic and spiral springs. (Notshown) Aspring-plankcomposed oftwo spaced bars G is carried by links H at each side of the truck, whichlinks are supported at their upper ends by pins It, resting in socketsin connection with the transoms, and at their lower ends providebearings for a pin which passes through a sleeve h in connection withthe two bars of the spring-plank. Upper swivel-plate K pivots about thekingpin 76. Lower swivel-plate L, through which the king-pin passes, ishingedly mounted with respect to the bolster bylugs Zdependingtherefrom, in which is loosely journaled transverse pin Z, which in turnis supported by lugs or ears Z upon a casting Z riveted within thebolster. These parts are only shown at one end of the bolster; but theyare all of known construction, and inasmuch as they are only illustratedin explanation of the essential features of my invention it is thoughtthat such illustration is sufficient.

Brake-rod 1, which may be actuated in any suitable way, is connectedsubstantiallyat the center of a transverse bar 2, at each end of whichis pivotally connected downwardly-extending levers 3. Inasmuch as thebrake mechanisms at each side of the truck, which are actuated throughbrake-rod 1 and bar 2, are duplicates, the description of such mechanismon one side of the truck will suflice for both. Lever 3 is pivoted inbrackets or supports 4: on a pin 1'. Brackets 1 are carried oncross-beam 5, rigidly secured at its ends to the side bars, as indicatedin Fig. 3. This cross-beam provides a rigid support on which the variousmoving levers of the brake mechanism are fulcrumed. Near the lower endof the lever 3 is pivotally connected a clevis or coupling 6, which isbifurcated vertically to embrace said lever 3 at one end andtransversely at the other end to embrace the lever 8, which is pivotedthereto between its center and its inner end by the pin 7. Said lever 8is pivotally mounted at its outer end upon the pin 9 within clip 10,which is secured in any desirable manner to the brake-beam 11, whichcarries the brake-shoes 12 for the smaller set of wheels. Theconstruction illustrated is one in which the brake-shoes are hung uponthe inside of the wheels, forming what is known as an insidebrake-rigging; but it will be understood that with slight changes theinvention ""---.might be adapted to an outside brake-rigging.

At the inner end of lever 8, by means of pin 13, is pivotally mountedthe bifurcated end of lever 14, the other bifurcated end of which ispivotally connected by the pin 15 to the end of the lever 16, which ispivoted at 17 to a bracket 18, secured to the rigid cross-beam 5 andextending toward the side of the larger wheels. To the outer end oflever 16 by the pin 19 is pivotally connected clip 20, to which isconnected the rod 21, which passes through brake-beam 22, carrying thebrake-shoes 23 for the large wheels. This connecting-rod 21. isscrew-threaded throughout a portion of its length and is adjustablysecured in position in connection with the brake-beam 22 by washers 2aand nuts 25, located on said threaded rod on each side of thebrake-beam.

It will be understood from the above description that a pull upon bar 2through the brake-rod 1 will throw the levers 3, extending downwardlytherefrom at each end, and these levers through the connecting clevis orcoupling 6 and the various connecting-levers will throw both brake-beams11 and 22 in order to set the brake-shoes against the wheels. It isimmaterial whether the action of the two brake-beams is defined astaking place simultaneously or in succession. The action of the saidbrake mechanism will be practically to set all the brake-shoes at thesame time. Any desired ratio of braking pressure between the large andsmall wheels may be obtained by proper positioning of the pivotal pointsof the several levers. The construction shown is one which has beenfound efiicient for this purpose, the pivotal point of the clevis 6 withrelation to the lever 8 being such as to properly divide the pressure. I

thus provide a construction wherein without the use of any springs orcompensating yielding members but simply by the proper proportioning ofthe long and short arms of the various levers, a pull upon the brake-rodtransmits a differential pressure to the large and small wheels. Suchconstruction is eificient in attaining the desired results and has noparts which are likely to break or get out of order.

Having described my invention, what I claim as new, and desire to secureby Letters Patent, is-

1. In a brake mechanism for a truck, in combination with the usualbrake-shoes and brake-beams, a lever pivotally mounted upon one of saidbeams, a lever connected to actuate the other of said beams and alsoconnected to said first lever, and a member connected to said firstlever between its center and the point of attachment of said secondlever, which member is adapted to be actuated from the brake-rod.

2. In combination, in a maximum-traction truck, large wheels (1, smallwheels D, brakebeams 22 and 11, respectively, adapted to carry thebrake-shoes for said wheels, the lever 16 pivoted to a point of supportin con nection with the truck-frame, a connectingrod between said leverand brake-beam 22, the lever 8 mounted on brake-beam l1, lever 14connecting said levers 8 and 16, a brakerod and connections from saidbrake-rod whereby power is applied to the lever 8 between the centerthereof and point of attachment of the lever 14 thereto, substantiallyas and for the purpose described.

3. In a maximum-traction truck, the combi nation with the usual largeand small wheels and the frame, of the brake-beams 22 and 11 adapted tocarry brake-shoes respectively for the large and small wheels, brake-rod1 and means for actuating said rod, transverse bar 2 connected thereto,levers 3 connected to the ends of said bar 2 and pivotally mounted oncross-beam 5, couplings 6, levers 8 pivotally mounted upon thebrake-beams 11, levers 16 pivoted upon the cross-beam 5, connectingrodsbetween said levers and brake-beams 22,

and levers 1 L connecting the ends of levers 8 and 16, substantially asdescribed and for the purpose set forth.

4. In braking mechanism, in combination, a truck-frame, a plurality ofpairs of Wheels, a brake-beam corresponding to each pair, each beambeing provided with shoes adapted to engage the corresponding wheels, apair of levers pivotally connected with one of said brake-beams, asecond pair of levers having a pivotal mounting in fixed relation tosaid truck-frame, connections between said first and second mentionedlevers, connections between said second-mentioned pair of levers andanother of said brake-beams, and means adapted to apply power to saidfirst-mew tioned pair of levers, said levers, connections, andbrake-beams lying substantially within a single plane.

5. In braking mechanism, in combination, a plurality of pairs of wheels,a brake-beam corresponding to each of said pairs, each of saidbrake-beams being provided with shoes adapted to engage thecorresponding Wheels, a pair of levers connected with one of sa dbrake-beams, a second pair of levers, connections between said first andsecond mentioned pairs of levers, connections between saidsecond-mentioned pair of levers and another of said brake-beams, andbrake-applying means connected with said first-mentioned levers at suchpoints as to actuate said brake-beams with a force corresponding to theloads upon the corresponding Wheels, said levers, brakebeams, andconnections lying substantially within a single plane.

In testimony whereof I atfix my signature in the presence of twoWitnesses.

BURTON R. STARE. WVitnesses:

FREDK. R. OAsE, JOHN K. BOSTWIOK.

